Machines such as, for example, dozers, motor graders, wheel loaders, and other types of heavy equipment are used to perform a variety of tasks. Some of these tasks require very precise and accurate control over operation of the machine that are difficult for an operator to provide. Other tasks requiring removal of large amounts of material can be difficult for an unskilled operator to achieve efficiently. Because of these factors, the completion of some tasks by a completely operator-controlled machine can be expensive, labor intensive, time consuming, and inefficient.
One method of improving the operation of a machine under such conditions is described in U.S. Pat. No. 5,375,663 (the '663 patent) issued to Teach on Dec. 27, 1994. The '663 patent describes an earthmoving apparatus and method for grading a tract of land to a desired finish contour. The earth moving apparatus has a blade of known width for cutting and filling soil. Vertical blade movement and the x and y position of the earthmoving apparatus are continually detected by sensors as the earthmoving apparatus traverses the tract of land. An ultrasonic transmitter and receiver detects elevation of the soil to provide updated soil elevation information. A computer uses this information to generate a contour map of the tract of land with fill and cut lines thereon that will produce the desired finish contour. The computer continuously modifies the contour map to reflect changes in the topography of the tract of land as the earthmoving apparatus proceeds with the grading process. In addition, the computer generates an elevation error based on the contour map and a detected position of the blade. The computer then automatically adjusts elevation of the blade to reduce the elevation error.
Although the computer of the '663 patent may improve precision and accuracy of the earthmoving apparatus during a grading process, it does not consider removal parameters that can affect efficiency. In particular, the computer does not consider the amount of material to be removed during a single pass, the uniformity of the material, the size or shape of encountered obstacles, or the removal capacity of the earthmoving apparatus. Because the computer of the '663 patent does not consider these removal parameters, it may be inefficient at removing large amounts of material or non-uniform material from the tract of land.
The disclosed system is directed to overcoming one or more of the problems set forth above.